Method and apparatus for treating materials



Dec. 21, 1937. D. s. BAKER METHOD AND AFPARATUS FOR TREATING MATERIALS Filed April 17 1934 3 Sheets-Sheet 1 firmvron MA- XI. 731 /14,

A o EY Dec. 21, 1937. BAKER 2,102,507

METHOD AND APPARATUS FOR TREATING MATERIALS Filed April 1'7, 1934 3' Sheets-Sheet 2 INVENTOR AQMA ,4. M

17' RNEY 21, 1937. .5 5, BAKER 2,102,607

METHOD AND APPARATUS FOR TREATING MATERIALS Filed April 17, 19:54 3 Sheets-Sheet s v INVENTOR fiawzd. A. fin-up' @4017 I4. Edy/v ATTORNEY Patented Dec. 21, 1937 UNITED STATES 7 2,102,607 METHOD AND APPARATUS FoR TREATING MATERIALS David S. Baker, Greenwich, Conn.

Application April 1'1, 1934, Serial ld'o. 720,944

27 Claims.

be used to advantage,,for example, in heat treating finely divided materials such as grains and the like.

Heretofore devices have been used in which the material to be treated is rotated within a hollow drum. This method is subject to several disadvantages. The material in the drum tends to form into balls, the outside of which become hardened, preventing the drying of the material within the balls. Where the treatment consists in drying the material, difliculty is experienced due to the dusting of the material after it becomes partially dry.

My invention makes it possible to overcome the diflicuities heretofore experienced, and, at the same time materially decreases the time required for treating the material, and otherwise effects a substantial economy.

In accordance with my invention, the material to be treated is repeatedly and alternately (1) formed into a layer adapted to be efiiciently heated or cooled, and (2) broken up and disintegrated so that it may be acted on by the atmosphereor other gas. These operations are repeated until the desired conditions of temperature of moisture content, or both; have been attained. t

Theterm drum dryer is used herein to indi cate the class of drying apparatus in which the 4 plied to the internal surface of the drum and the material to the outside surface of the drum. In 50 the internal or rotary dryer the heat and the material are both-applied to the same surface.

Moistureis free to escape from'the-drum dryer along lines perpendicular to the/axis of rotation of the drum. In the internal or rotary dryer 55 the moisture cannot escape directly but must pass The latter along the surface of the rest of the material on a line substantially parallel'to the axis of rotation of the kiln.

While the exact mechanical arrangement of the parts of my device is subject to wide varia- 5 tion, I have, for the sake of illustration, shown in the accompanying drawings specific embodiments of my invention whereby the material to be treated may be supplied either intermittently in separate measured batches or continuously. 10 Otherobjects and advantages of my invention will be apparent if the following detailed description and the claims appended thereto are read in connection with the drawings in which:

Fig. 1 is a vertical cross-section of my appa- 15 ratus; 1

Fig. 2 is a detail view of the measuring, applying; and removing means illustrated in Fig. 1;

Fig. 3 is a fragmentary-view illustrating the action of the material removing means; 20

Fig. 4 is a vertical sectional view of a modification of my device employing a plurality of material receiving surfaces;

Fig. 5 is a fragmentary view, showing a modification of the surface illustrated in Fig. 3;

Fig. 6 is a vertical cross-section of another form of my apparatus; I

Fig. 7 is a front plan view, partly in cross-section of the form of my apparatus shown in Fig. 6; and

Fig. 8 is a vertical cross-section of the cylindrical receiving member forming part of the embodiment of my invention illustrated in Figs. 6 m and '7.

Referring now to the drawings, the numeral l 35 refers to a hopper from which material to be treated is supplied to the rotary cylinderv 2 and transferred thereby to the surface of the rotary cylinder 3, the temperature of which, if desired, may be controlled by any suitable means such as 40 the steam connection 4 admitted to the interior of the cylinder through the trunnion 5. The rotary cylinders 2 and 3 are adapted to rotate inwardly with respect to one another and are so positioned relatively that the scrapers 6a, 6b, 6c, and 6d may be positioned adjacent the surface of the member 3 and in the pathway of material thereon; and, at the same time, be positioned directly above the member 2. Material separated from the member 3 by the scrapers 6a, 6b, 6c and [id is, therefore, returned by gravity to the surface of the member 2 and re applied to .the surface of the member 3. In this way the material is continually broken up and exposed to the material, air or'other gas under pressure may be applied to the material, preferably just after it is broken up and removed from the retaining surface. I

It will be noted that the scrapers 6a, 6b, 6c, and Gd-are arranged at different distances from thesurface of the member 3, thereby more effectively breaking up the material on the surface of the member 3 by removing it in successive layers as illustrated in Figs. 1 and 3.

When the material being treated has attained a predetermined condition, or for any reason it is desired to terminate the successive operations of applying the material to the surface of the member 3 and removing it therefrom the member If! is interposed between the member 2 and the scrapers 6a, 6b, 6c, and 6d and the separated material-is diverted thereby to the screw conveyor H by which it is evacuated from the casing 1. I

Within the hopper [,a valve member I2 is provided which is opened to admit material to the surface of the member 2, but which is closed when the spacebetween it and'the surface of the member 2 has become filled, thereby permitting only a predetermined or measured amount of material to be supplied to the surface of the member 3.

Any suitable means of feeding, spreading, depositing or otherwise applying material to the surface of the member 3 may be used, but I have found it particularly desirable to use the feedin means fully set forth and claimed in my 00- pending application for Letters Patent of the United States, Serial No. 713,117, filed February 27, 1934. Since the feeding means per se forms no part of my present invention, I will describe it only briefly herein. The hollow rotatable member 2 isprovided with a number of radial vanes 13 adapted to be projected through apertures in its periphery, and each of said vanes is provided with a cam roller l3a mounted in a cam race l4 whereby the vanes are projected during the portion of each revolution of the member 2 when members 2 and 3.

they are travelling through the space enclosed by the hopper I, but are withdrawn before reach ing the point of closest approach between the The vanes 3 serve to engage the material in the hopper and force it against the surface of the member 3 and into the grooves 95 provided thereon. The wire I6 is positioned adjacent to and extending longitudinally across the surface of the member 2 below the point of closest approach to the member 3, to separate material adhering to the surface of the member 2, this means having been found to be particularly desirable as is explained more fully in my said co-pending application.

As illustrated herein the grooves l5 provided on the surface of the member 3 are substantially v-shaped. This structure has the advantage of bringing a. maximum surface in contact with the material being treated, which is of obvious advantage in any operation involving the transfer of heat. Since in the operation of my invention, the material receiving surface is heated internally and the material to be treated is applied externally, the material itself serves to insulate'the heated surface, thereby greatly reducing the amount of heat consumed,

different surfaces.

it is desirableto use a surface having compara tively wide material-receiving grooves, such for example as those numbered 15 in Fig. 3, until a portion of the moisture content has been removed,

and to complete the operation on a second sur I face having grooves which are deeper and narrower in cross-section, such, for example, as those numbered IT in Fig. 5.

It may also be desirable in some instances to modify either the heat applied to the material or the frequency with which the material is removed from the surface. Thus, for example, it may be desirable to apply the material to a surface heated to a high degree and moving at a low rate of speed, while said material retains a high percentage of moisture, but, when the moisture content has been reduced, it may be found that under these conditions the material is becomin overheated. Overheating may be avoided either by increasing the frequency with which the material is removed from the surface, or by reducing the temperature of the surface, and one way of accomplishing this is to transfer the material from one surface to another having a different temperature or speed.

A modified form of my device employing a plurality of surfaces is illustrated in Fig. 4. The material is supplied through the valve l2 in the hopper I to the feeding member 2 by' which it is applied to the external surface of the member 3,

which is supplied with-a heating medium through grooves 15 on the surface of the member 3 and carried through a portion of the rotation of the member 3 until .it is removed therefrom by the scrapers 6a, 6b, 6c, and 6d arranged at spaced intervals from the surface of themember 3, for the reasons set forth above. The material, after being removed from the member 3, is returned by gravity to the member 2 and re-applied to the surface of the member 3, and these operations are successively repeated until the material has attained the desired conditions of temperature and moisture content or until it is, for any reason, desired to transfer the material to another'surface.

The transfer is accomplished by projecting the movable scraper 18 into the path of the material on the member 3 intermediate the member 2 and the scrapers 6a, 6b, 6c, and 6d, therebyremoving the material from the member 3. The separated material is transferred by gravity to the feeding member 22 by which it is applied to the surface of the member 23. The material is carried on the surface of the member 23 until itis removed therefrom by the scrapers 26a, 26b, 26c, and 26d, and returned by force of gravity to the feeding member 22 to be re-applied tothe surface of the member 23. These operations are repeated until the treatment of the material is completed or it is desired for any reason to remove the material when the movable separating means |8a is projected into the path of the material on the member 23 intermediate the member 22 and the separating means 26a, 26b, 26c, and 26d, and the separated material is directed to the conveyor H by which it is evacuated from the casing 21.

All of the operations described herein may be performed by automatic means as will be readily understood by those skilled in the art. Thus, for example, automatic timing means may be'provided so that the member III will be automatically closed atapredetermined time, thereby diverting the material to the conveyor ll to be evacuated from the casing, and it is to be understood that either automatic or hand-operating means are within the scope of my invention.

- In the embodiments of my invention described above, the material to be treated is supplied interthereby to a corresponding portion of the surface of the rotary cylinder 33 and is rotated .thereon until it is brought into contact with the scrapers 6a, b, 6c, and Ed, by ,which it is separated from the said surface and broken up. Instead of dropping back onto the portion of the member 2 to which it was first supplied, the separated material falls upon the first of a series of deflectors 34, by which it is advanced to the portion of the member 2 adjacent. to the portion to which it was originaliy supplied, and is applied to the corresponding portion of the surface of the rotary cylinder 33. The steps of-separating, advancing and'applying the material are repeated until the mate-' rial has been advanced across the entire length of the receiving surface, and the treated material is then discharged into the conveyor 1 I.

In order to eliminate the necessity for transferring the material from one receiving surface to another to vary the condition of temperature, the interior of the cylindrical member 33 is divided into a plurality of chambers by the partition 35, and differentially heated mediums are supplied to and removed from said chambers by the conduits 4a and 4b, and 4c and 4d, admitted to the interior of the respective chambers through the tru nions 5 and 5a.

As illustrated in Fig. 8, the material retaining grooves 36 are made progressively narrower from the point where the material is first applied to I the receiving surface to the point where the treated material is discharged. This structure corresponds in a general way with the diminishin, moisture content of the material being treated and enables the progressively dried material to' be retained on the samereceiving surface.

It is desirable that the deflectors 34 be mounted in any suitable way permitting the angle of deflection and the number of deflectors employed to be varied so that the number of times that the material is separated from'the receiving surface and thetime required for traversing the surface may be adjusted to the character and condition of the material being treated. As shown inFig. 6,

thedeflectors' 34 are mounted on the casing I.

By mounting each of the deflectors at its lower end on a pivot 38 and providing itat' its upper end with a thumb= screw 39 engageable in a slot 40,.

grating said units and redistributing the material comprising the units between applications to said surface.

2. A drum dryer, comprising a rotary cylinder,

means for repeatedly applying the material to the surface of the cylinder at one point .of its periphery, means for attempering said -surface, means for scraping the material from the surface of the cylinder and disintegrating it located at another point of the periphery of the cylinder,

.and means for directing the disintegrated mate rial from the scraping means to the applying means.

13. A drum dryer comprising a grooved receiving surface, means for' attempering said surface, means for applying material to said surface, means'for breaking up and removing the material from said surface, and means for returning and re-applying the separated material to the same surface.

' 4. A drum dryer comprising, a grooved material receiving surface, means for attempering said surface, means for applying material to said surface, material removing and-disintegrating means positioned adjacent to said receiving surface, means for causing relative movement between said-surface and said removing means to separate the material from said surface, and-means including said applying means for returning the separated material to the same surface.

. 5. Apparatus for attempering plastic material, comprising two adjacent cylinders rotated in opposite directions to transfer the material from the external surface of the first cylinder to the external surface of the second cylinder, means for attempering'the surface of said second cylinder, scrapers positioned within the path of the material on said second cylinder, and means for returning to said. first cylinder material separated from the second cylinder by said scrapers,

6. In apparatusfor treating material, the combination of a-receiving surface, amaterial applyof said member, vans projectible from the peripheral surface of sai'd'member, 'means for pro- -jecting each vane'while it is within said hopper and for withdrawing it before it reaches the closest point between said member and said surface, and means for separating the material from said surface and returning it to said member.

7. In apparatus for treating material, the combination of a. receiving surface, a rotary material -applying member positioned adjacent said surface, means for supplying material tosaid member, means on said member for pressing material onto said surface, a wire positioned adjacent the surface of said member just below the point of material to the external side of said surface,

means for' applying a temperature modifying medium to the inner side of said surface, material removing means positioned above said applying means and adjacent to said receiving surface, means for causing relative movement be- --tween said surface and said -material removing means to separate the material from said surface, and means for returning the. separated material to said applying means.

9. A drum dryer comprising in combination of 'a grooved attempering surface, means for supplying a temperature controlling medium to one side of said surface, means for applying material to the other side of said surface, and means including said applying means for removing the material from said surface, disintegrating it and returning it to said surface.

10. A drum dryer comprising in combination a rotary cylindrical member having an external attempering surface, means for attempering said surface, means for applying material to said surface, means for breaking up and removing the,

' said path to transfer the material to the applying means associated with the second cylinder.

12. In apparatus for treating material, the combination of a plurality of differentially heated receiving surfaces, means for alternately applying the material to and removing it from one of said surfaces, means for. transferring the material to the other of said surfaces, and means for alternately applying the material to and remov ing it from said other surface.

13. In apparatus for treating material, the combination of a plurality of differentially scored receiving surfaces, means for alternately applying material to and removing it from one of said surfaces, means for transferring the material to the other of said surfaces, and means for alternately applying the material to and removing it fromsaid other surface.

14. In a drum dryer, the combination of a re- ,ceiving surface, means for attempering said surface, means for continuously supplying material to one portion of said surface, means for separating the material from said surface, means for changing the position of said material relatively to said receiving surface, and means for re-applying the material to another portion of said surface.

15. In a drum dryer, the; combination of an attempering surface, means for differentially attempering different portions of said drum, means for continuously applying material to one portionof said surface, and means for progressively advancing the material parallel to the axis of rotation of said surface in a series of steps, each of which includes separating material from said surface and reapplying it to said surface.

16. In a drum dryer, the combination "ofan attempering surfacehaving differentially scored portions, means for continuously applying material to one portion of saidsurface, and means for progressively advancing .the material upon said surface.

17, In a drum dryer, the combination of an attetnpering surface, means for attempering said surface, means for applying material to said surface, means for separating the material from said surface, and means interposed between said separating means and said applying means for intercepting the separated material, advancing it laterally of said surface, and returning it to said applying means to be re-applied'to said surface.

18. The method of attempering material which comprises repeatedly removing. the material from an attempering surface onto a second surface adapted to receive material separated from said attempering surface and to transfer it onto said attempering surface, including an intermediate step of separating the material and retuming it to the second surface. 1

19. The method of attempering plastic mate rial which comprises repeatedly molding the material in some of a series of molds contained in an attempering surface, attempering said surface, removing the material fromflsaid molds, disintegrating it and advancing it along the said surface and remolding it in some of the molds contained in said attempering surface.

5 20. A drum dryer comprising a grooved at-' tempering surface,means for attempering the said surface, means for pressing material to be treated into the grooves of said surface, means for separating the material from said grooves.

means for advancing the material along the face of said dryer and for returning it to said means for pressing material into the grooves tr said "surface to be retreated upon said surface.

21, The method of attempering material which comprises molding it in a number of molds in the periphery of a drum dryer, supplying an attempering medium to the under faces of saidmolds, removing the material from the molds,.

disintegrating it, and automatically returning it to the same drum dryer and remolding and reattempering it.

22. The method of drying materials which comprises applying the material to the outer periphery of a cylindrical surface in units of substantially equal width, disintegrating .the

. material and re-applying it as before to the same surface in a continuous operation.

23. The method of attempering plastic material which comprises applying the material to the external surface of a revolving drum, attem-.

pering the said surface, separating the material from said surface and disintegrating it, advancing the material along the axis of rotation of said"drum and re-applying it to the external surface of the same cylinder.

24. The method of attempering plastic mate-.

the external surface of a rotary cylinder and confining it in concavities in said surface, attemp'ering the material on a plurality of sides, removing the material from said concavities and disintegrating it, advancing the material along the axis of rotation of said cylinder and ,re-applying it to the external surface of the same cylinder and re-confining it in concavities in the surface of the same cylinder.

25. A drum dryer having means for enmeshing material on its surface, means for attempering said surface, means for molding material upon said surface into units of predetermined rial which comprises applying the material to shape, means for intermittently removing and disintegrating the material; adjustable means for advancing said material a predetermined distance along the surface of said drum in a. direction substantially parallel to the axis of rotation of said drum, and means for returning the dis-.

integrated material to the same drum andreforming the material thereon into units of predetermined shape.

26. A drum dryer having means for enmesh ing material on its surface, meansfor' attempering said surface, means for molding material upon said surface into units of predetermined shape, means for intermittently removing and disintegrating the material, means for advancin; the disintegrated material along the surface '0! the drum in va direction substantially parallel' 15o the axis of rotation of said drum, and means for returning the disintegrated material to the same drum and re-forming thematerial thereon into units of predetermined shape.

27. Apparatus for attempering material having an externally grooved attempering surface,

andmeans for applying material to said attem- DAVID s. BAKER.- 

